Overview

Raised bed and garden

The stone wall and flagstone path blend perfectly into a lush garden setting.

Natural stone

The rough, randomly stacked stone softens with time and weathering, growing more attractive as it ages.

If one of your family members loves plants and
flowers, why not build this raised bed? It not
only allows you to get just the right soil mix
for healthy plants but also reduces back strain, because
you don't have to bend over so far to tend it. The natural
stone walls also look great and are easy to build.

In this story, we'll show you the easiest, most time-efficient
way to build a stone planter that will last for
decades. We'll also offer tips for sorting and placing stones
so you end up with great-looking stonework. You can use
these techniques to build a raised garden bed of any shape
and size.

This project doesn't require any special skills, but it
does require a bit of muscle to lift the stones. The only
specialty tool you'll need is a diamond blade (sold at home centers) in your circular saw. Our 4-ft. x 16-ft. planter took two of us about 16 hours to complete.

Plan your raised bed

Start by marking the planter outline on the ground, using a rope
or garden hose. Dry-stacked walls like this are limited to 3 ft.
in height or they could tip over. Call to have underground
utilities marked in your yard before you
dig and before you have materials delivered, in
case you have to move your wall location. The
North American One-Call Referral System
number is 811.

Once you determine the shape and size of
the structure, you can order the materials.
Take your dimensions with you to the
stone supplier, who can help determine
the quantities of stone, pea gravel, landscape
fabric and topsoil you'll need. Order
10 percent extra stone so you have plenty
to choose from. You can always use leftovers
for borders around gardens.

Browse suppliers to find a stone you
like (selections are often regional). Costs vary
a lot among stone types. We used a stone called
weathered Chilton. We needed three tons of the stone, a yard of
pea gravel and three yards of topsoil. You can
use a different (and less expensive) stone, as long as it's relatively
flat on the top and bottom. The more flat-surfaced and square the
stones are, the easier they are to stack. The techniques we show
won't work for rounded fieldstone. You can buy capstone, which
is a special stone for the top course, or use the same stone as for
the rest of the planter.

When you're ordering materials, ask about delivery fees and
forklift services. It's worth the extra forklift charge to
have the materials placed right next to the work area. Trust me on
this. Our driver couldn't get his forklift to the backyard at our
location, so we had to move everything by wheelbarrow (it took
more than 50 trips!).

Figure A: Raised Bed Details

Build the wall on a gravel base for stability and drainage, and cover the back with landscape fabric and more gravel before filling in with soil.

Sort stones by size

To make placing stones easier, first arrange them into groups
based on similar thicknesses and lengths. As you sort them, set
aside nice-looking stones to use as capstones. Keep their thicknesses
within a 1/4-in. variation. We set aside 3-1/4-in.- to 3-1/2-
in.-thick stones for our capstones.

Spread out the stones on tarps, rather than stacking them, if
you have room. It'll save you from digging through the piles later
to find the stones you want.

Dig the trench and add gravel

Photo 1: Dig the trench

Mark the border of the raised bed with a rope. Dig an
8-in.-deep x 10-in.-wide trench next to the rope. Level
the bottom and create steps to accommodate sloped areas.
Fill the trench with 4 in. of gravel.

Photo 2: Lay the first stones

Set stones on the
gravel and check for
level. Add or remove
gravel to form a level
base all along the trench.

Dig a trench alongside your hose or rope, starting at the lowest
point. Use a square shovel for crisp edges and keep the trench bottom
roughly level. Dig the trench deep enough to hold 4 in. of
gravel and still bury at least half the first course of stone.
If the yard slopes, gradually “step up” the trench to follow the
slope (Photo 1). Make the steps match the thickness of the stones
you'll use for the first course of stone. Toss the soil from the
trench into the middle of the planter area for use as backfill later.

Once the entire trench is dug, add 4 in.
of pea gravel. As you add the gravel, place
a stone over the top every foot or so and
check for level (Photo 2). Add or remove
gravel (a little at a time) as needed until
it's roughly level. You'll fine-tune it when
you install the first course of stone
(called the “base course”).

Lay landscape fabric and the base course

Photo 3: Anchor landscape fabric

Lay landscape fabric
over the gravel
(Figure A), then place the
base course of stones
over the fabric. Check
the stones for level. Add
gravel under low stones
and pound down high
stones. Butt the outside
edges of the stones
tightly together.

Photo 4: Start the second course

Add a second course
of stones, mixing sizes
and staggering the joints
from the base course.
Keep the joints tight on the exposed side.

Photo 5: Trim stones to fit

Use a 4-lb. hand maul
and masonry chisel
to knock “burrs” off the
stones so they fit more
tightly together.

Roll out landscape fabric along the
trench, keeping one edge of the fabric in
the center of the trench. Temporarily
weigh the fabric down with stones to
keep it in place.

Next, install your base course of stone
over the edge of the landscape fabric and
the gravel. Use the less attractive stone
for the base because it'll be hidden by soil
and grass. Check every couple of stones
for level. Pound down high stones with a
rubber mallet, and add gravel under low
stones, placing the gravel on top of the
fabric (Photo 3).

For good-looking stonework, avoid
large gaps between stones on the exposed
face of the wall (Photo 4). To get a tight
fit, knock off protrusions (called “burrs”)
with a masonry chisel (Photo 5). Don't
worry about gaps inside the wall; they
won't be visible.

You'll have to cut some stones to fit.
Mark the stone and, using a diamond
blade in a circular saw, make a series of
cuts about 1/8 in. deep along your mark,
lowering the blade with each pass until
you're one-third of the way through the
stone. (To limit dust, have a helper squirt
water from a spray bottle on the blade
while you cut.) Then flip the stone over
and cut from the opposite side. The cuts
don't have to be perfectly aligned. Tap the
waste side of the stone with the maul to
break it off. Save the leftovers for filler.

Stack stone randomly and backfill gradually

Photo 6: Backset stones

Backset each row
about 1/2 in. from
the course below. Break
up courses with thick
“jumper” stones to
create a random pattern.

Photo 7: Backfill

Lift up the landscape fabric and
backfill inside the planter every
couple of courses.

Once the base course is installed, lay the
remaining courses, except the capstone. Offset joints between courses to give the walls greater strength and to achieve a
more pleasing look. Mix stone height,
length and color as you lay the stones.
Place exceptionally thick stones (called
“jumpers”) where you want to break up a
uniform pattern (Photo 6). Backset each
course about 1/2 in. inside the previous
course so the wall slopes slightly inward.

The toughest part of building the
planter is laying the stones in an attractive,
yet seemingly random, pattern. We often
set a stone in place, then moved it several
times to find the best fit. Grab stones from
different piles (except the capstone pile)
for each course to ensure a mix of lengths
and thicknesses. Take your time and don't
hesitate to take a section of wall apart to
redo it if it doesn't look good.

As you complete every couple of
courses, pull the landscape fabric tight
against the stones and shovel backfill
(topsoil) against the walls (Photo 7).
Backfill to the top of the last installed
row. This helps hold the stones in place.

Level the last course and dry-fit the capstones

Photo 8: Set and mark capstones

Set capstones in
place, overhanging
the other courses by
2 in. Mark the stones
and cut them to create
tight joints.

When you're laying the final course,
patiently select and place stones so the
top of the entire course is flat and level
(the stones should be within 1/4 in. of
level with adjacent stones). That way, you
can more easily lay your capstone flat and
level. Place a straight 10-ft. 2x4 over the
last course as you lay the final course to
check for level.

Now use a utility knife to trim the
landscape fabric, making it cover the last
course of stone by about 4 in. (Photo 9).
Then install the capstones so they slightly
overhang the underlying courses. We
made ours overhang 2 in. Leave gaps at
least 1/4 in. wide between capstones so
you can tuck mortar between them. But
avoid gaps more than 3/4 in. wide
because they'll look bad.

To cut them to fit, place the first two
capstones on the wall. Use a straightedge
to mark roughly parallel lines on
both stones so the edges will match
(Photo 8). You don't have to make this
cut perfect; mortar will fill the gap
between them. After you cut them to
size, set them in place.

If two capstones fit nicely along the
outside edge but leave a large gap on the
inside, fill the gap with a wedge of stone
(cut to fit if necessary) rather than cutting
off large sections of capstone. If the
gap-filling stones aren't as thick as the
capstone, make up the difference by piling
more mortar beneath them.

Setting capstone is a time-consuming
process, since you have to mark, cut and
dry-lay them one at a time. The positions
of the capstones will change slightly after
cutting, so mark and fit them one at a
time all along the wall.

Mortar and tuckpoint the capstones

Photo 9: Mortar the capstones in place

Remove a few
capstones at a time
and lay a 1/2-in.-thick bed
of mortar over the back
half of the wall. Fold the
fabric over the mortar.
Add another 1/2 in. of
mortar, then set the
capstones in place.

Photo 10: Fill the joints

Pack mortar into
the joints on the
top and front of the capstones.
Brush off crumbs
of mortar after they dry.

After dry-laying the capstones, apply
mortar to permanently hold them in
place. Mix one bag of mortar with water
in a wheelbarrow until it's the consistency
of peanut butter, then put some in a
5-gallon bucket. Like any cement-based
product, mortar can burn your skin, so
wear gloves.

Remove a few capstones from the
planter, then apply mortar, both under
and over the landscape fabric (Photo 9).
Set each capstone back on the wall,
pressing it into the mortar. Work in sections
of two or three capstones at a time
so the mortar doesn't dry out on the
wall. Mortar and set the entire course
of capstone.

Then go back and fill the joints with
mortar (Photo 10). Scoop the mortar
onto one trowel, and use a second trowel
to push the mortar into the joints, slightly
overfilling them.

Let the mortar dry, then use a whisk
broom or a wire brush to brush away
any that has splashed onto the stones. If
you discover stains later, scrub them
away with a diluted mix of muriatic
acid.

Allow the mortar to set overnight
before topping off the planter with soil
and mulch. Then fill it with the flowers
of your choice!